如何获得两个用户之间聊天转换的最新记录？

Question

=>我想基于创建日期字段获取两个用户之间的聊天转换的最新记录，以获取最新消息。下面是我的桌子

我尝试使用此查询来获取聊天转换的最后一条消息的结果，但我无法获得正确的结果。

select `chat_messages`.`id`, `chat_messages`.`message`, `chat_messages`.`created_at` 
from `chat_messages`
where `chat_messages`.`is_group` = 0 
and `chat_messages`.`deleted_at` is null 
and (`sender_id` =141 or `client_id` = 141)
group by `chat_messages`.`message_token` 
order by `chat_messages`.`created_at` desc

=>当前结果：-

=>应该是：-

注意：-此功能类似于聊天功能，我不想只获得一条记录。

谢谢。

Answer 1

group by导致了您的问题。您需要做的是对desc排序，然后将结果集限制为一行

select `chat_messages`.`id`, `chat_messages`.`message`, `chat_messages`.`created_at` 
from `chat_messages`
where `chat_messages`.`is_group` = 0 
and `chat_messages`.`deleted_at` is null 
and (`sender_id` =141 or `client_id` = 141)
order by `chat_messages`.`created_at` desc
LIMIT 1

Answer 2

为什么要按message_token分组？

我认为此查询将是有效的：

select `chat_messages`.`id`, `chat_messages`.`message`, `chat_messages`.`created_at` 
from `chat_messages`
where `chat_messages`.`message_token` = '144_141'
and `chat_messages`.`is_group` = 0 
and `chat_messages`.`deleted_at` is null 
order by `chat_messages`.`created_at` desc
limit 1

编辑后：

select `chat_messages`.`id`, `chat_messages`.`message`, `chat_messages`.`created_at`
from (select * from `chat_messages` order by `chat_messages`.`created_at` desc) as chat_messages
where `chat_messages`.`is_group` = 0
and `chat_messages`.`deleted_at` is null
and (`sender_id` =141 or `client_id` = 141)
group by `chat_messages`.`message_token`;

Answer 3

如果您按message_token分组，那么您将加入所有这些消息，则必须在where语句中选择该消息行，其中message_token = XXX。

SELECT 
    `chat_messages`.`id`, 
    `chat_messages`.`message`, 
    `chat_messages`.`created_at` 
FROM 
    `chat_messages`
WHERE 
    `chat_messages`.`is_group` = 0 
    and `chat_messages`.`deleted_at` is null 
    and (`sender_id` =141 or `client_id` = 141)
    and `chat_messages`.`message_token`= "146_141"
ORDER BY 
    `chat_messages`.`created_at` desc, 
    `chat_messages`.`id` desc

Answer 4

我假设您具有消息模型（您正在使用laravel）

下面的查询应该给您您想要的东西。

Message::whereSenderIdAndClientId($userId1,$userId2)
       ->orWhere([
             ["sender_id", $userId2],
             ["client_id",$userId1] 
         ])
       ->orderBy("created_at","desc")
       ->first()

获取发件人和客户端之间的消息，然后按created_at-desc的顺序对消息进行排序，然后采用第一个消息，即彼此之间的最后一条消息。